Crocodilia

Crocodilia and its characteristics

1. Crocodilia By: Dr Gul Muhammad FVAS Gomal University Dera Ismail Khan

2. Crocodilia Crocodiles Alligators Caimans Faculty of veterinary and animals sciences Gomal University DI Khan

3. Scientific classification Kingdom: Animalia Phylum: Chordata Class: Reptilia Order: Crocodilia Family: Crocodylidae & Alligatoridae

4. Family Crocodylidae Subfamily: Crocodylinae Genus: Crocodylus   Species: Crocodylus acutus (American crocodile) Crocodylus niloticus   (African crocodile) Crocodylus porosus   (saltwater crocodile)

5. saltwater crocodile   ( Crocodylus porosus ) Males 7.0 m (23.0 ft) in length weighing 1,000 to 1,200 kg Female : smaller as 3 m (9.8 ft) Habitat is mostly salt water

6. African crocodile ( Crocodylus niloticus) Also called Nile crocodile widespread throughout Sub-Saharan Africa. Adult male Nile crocodile is between 3.5 and 5 m and weighs 225 to 750 kg. Females are usually about 30 % smaller than males.

7. American crocodile

8.  H abitat American crocodile: found in coastal areas (transition areas between land and sea) and  in river systems. has a tendency to tolerate some level of  salinity. tolerance to salt water  is due to  salt glands  underneath the tongue. Also found on beaches and small island.

9. The American crocodile one of the larger crocodile species. Males: lengths of 6.1 m (20 ft ) and weighing up to 907  kg. Female: length 3.8  m (12 ft ) and weighing  about 400  kg.

10. Color Adults: uniform grayish-green coloration with white or yellow undersides. Juveniles: have dark cross-banding on the tail and back.

11. Diet  Fish, reptiles, birds and small mammals make up the majority of their diet. Occasionally, large mammals such as deer and cattle are taken. American crocodile is potentially dangerous to humans, though it tends not to be as aggressive as some other species.

12. Reproduction breed in late fall or early winter, engaging in drawn-out mating. Body size is more important than age in determining reproductive capabilities. females reach sexual maturity at a length of about 2.8 m (9.2 ft). February or March, gravid females will begin to create nests of sand and mud.

13. Eggs Clutch size: 30 to 70 eggs . The white, elongated Eggs are 8 cm long and 5 cm wide and have a Number of pores in the brittle shell.

14. Incubation period 75- to 80-day

15. The hatchlings are 24 to 27 cm (9.4 to 10.6 in) in length They are actively hunt prey within a few days of hatching

16. Group of crocodile is called Bask

17. Body Characteristics Scaly hide with rows of ossified scutes running down its back and tail. (scute  or  scutum is a bony external plate or scale ) Snout is elongated and includes a strong pair of jaws. eyes have nictitating membranes for protection along with lacrimal glands, which produce tears.

18. Cont… Nostrils, eyes, and ears are situated on the top of its head so, The body can be concealed underwater for surprise attacks. Large American crocodile skull

19. Locomotion Crocodile species normally crawls on its belly, but it can also "high walk". can swim at as much as 20 mph (32 km/h), By moving their bodies and tails in a sinuous fashion, but they cannot sustain this speed. Have a faster growth rate than alligators, and are much more tolerant of salt water.

20. Life span Saltwater crocodile: 70 years Nile crocodile: 70 TO 100 years

21. Conservation status American crocodile is endangered in parts of its range.  In 1972, Venezuela banned commercial crocodile skin harvesting for a decade, as a result of 1950s and 1960s overhunting. Because sex determination is temperature dependent in crocodilians, slight aberrations in temperature may result in all-male or all female clutches, which would possibly harm the health of the population.